Carrot (Daucus carota L.) is a nutritionally valuable root vegetable whose productivity is highly influenced by soil fertility and climatic conditions. The use of organic manures and appropriate sowing time plays a vital role in enhancing soil health, nutrient availability, and crop performance. A field experiment was conducted at the farm of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh, to evaluate the effects of different organic manure sources, such as (i) cow dung 20 t ha-1, (ii) poultry litter 12 t ha-1, (iii) vermicompost 10 t ha-1 and (iv) no organic matter (control); and sowing dates (i) 1st sowing (November 01), (ii) 2nd sowing (November 15), and 3rd sowing (November 30) on the growth and yield of carrot. The experiment was laid out in a randomized complete block design with three replications. The maximum plant height (47.4 cm), root length (21.5 cm), and yield (22.5 t ha-1) were recorded from organic manure, cow dung 20 t ha-1. For sowing time, maximum plant height (46.8 cm), root length (22.5 cm), and yield (22.6 t ha-1) were found in sowing on 15th November. In the case of the combined effect, the highest yield (28.7 t ha-1) was obtained from sowing on 15th November with cow dung 20 t ha-1, and the lowest (14.8 t ha-1) from sowing on 1st November with no organic matter.
Khan et al. (Thu,) studied this question.